On 09/06/16 10:10, Gregory CLEMENT wrote:
> From: Victor Gu <xigu@xxxxxxxxxxx>
>
> Some host controller such as Xenon needs additional setting when
> switching signal voltage in eMMC mode. They also need to re-enable
> internal clock before a voltage switch.
>
> This commit adds a callback routine "voltage_switch_pre" in the struct
> sdhci_ops, which is used by some host controllers which need re-enable
> the internal clock before a voltage switch.
Don't want to add sdhci host ops for the "do something before a mmc host op"
case.
Instead, export sdhci_start_signal_voltage_switch() and hook
host->mmc_host_ops.start_signal_voltage_switch. Then in sdhci-xenon.c:
int xenon__start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios)
{
blah blah
return sdhci_start_signal_voltage_switch(mmc, ios);
}
>
> [gregory.clement@xxxxxxxxxxxxxxxxxx: split the initial commit and
> reformulate the log]
>
> Signed-off-by: Victor Gu <xigu@xxxxxxxxxxx>
> Signed-off-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci.c | 4 ++++
> drivers/mmc/host/sdhci.h | 1 +
> 2 files changed, 5 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index b07219426d39..cad03ffa9d9b 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1729,6 +1729,10 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
> if (host->version < SDHCI_SPEC_300)
> return 0;
>
> + /* Some controller need to do more before switching */
> + if (host->ops->voltage_switch_pre)
> + host->ops->voltage_switch_pre(host);
> +
> ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
>
> switch (ios->signal_voltage) {
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 49c6c5b0e33b..6bec1b0368d2 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -550,6 +550,7 @@ struct sdhci_ops {
> unsigned int max_dtr, int host_drv,
> int card_drv, int *drv_type);
> void (*init_card)(struct sdhci_host *host, struct mmc_card *card);
> + void (*voltage_switch_pre)(struct sdhci_host *host);
> };
>
> #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
>
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
